package com.chinaway.dsp.util;

public class CoordinateConversion {
    public static double pi = 3.1415926535897932384626;  
    public static double a = 6378245.0;  
    public static double ee = 0.00669342162296594323;
    
    public static Point bd09_To_Gps84(double bd_lat, double bd_lon) {  
    	  
    	Point gcj02 = bd09_To_Gcj02(bd_lat, bd_lon);  
    	Point map84 = gcj_To_Gps84(gcj02.getWgLat(),  
        gcj02.getWgLon());  
        return map84;  
  
    }
    
    public static Point bd09_To_Gcj02(double bd_lat, double bd_lon) {  
        double x = bd_lon - 0.0065, y = bd_lat - 0.006;  
        double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * pi);  
        double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * pi);  
        double gg_lon = z * Math.cos(theta);  
        double gg_lat = z * Math.sin(theta);  
        return new Point(gg_lat, gg_lon);  
    }
    
    public static Point gcj_To_Gps84(double lat, double lon) {  
    	Point gps = transform(lat, lon);  
        double lontitude = lon * 2 - gps.getWgLon();
        lontitude-=0.00652;
        double latitude = lat * 2 - gps.getWgLat();
        latitude-=0.00605;
        return new Point(latitude, lontitude);  
    }
    
    public static Point transform(double lat, double lon) {  
        if (outOfChina(lat, lon)) {  
            return new Point(lat, lon);  
        }  
        double dLat = transformLat(lon - 105.0, lat - 35.0);  
        double dLon = transformLon(lon - 105.0, lat - 35.0);  
        double radLat = lat / 180.0 * pi;  
        double magic = Math.sin(radLat);  
        magic = 1 - ee * magic * magic;  
        double sqrtMagic = Math.sqrt(magic);  
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);  
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);  
        double mgLat = lat + dLat;  
        double mgLon = lon + dLon;  
        return new Point(mgLat, mgLon);  
    }
    
    public static boolean outOfChina(double lat, double lon) {  
        if (lon < 72.004 || lon > 137.8347)  
            return true;  
        if (lat < 0.8293 || lat > 55.8271)  
            return true;  
        return false;  
    }
    
    public static double transformLat(double x, double y) {  
        double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y  
                + 0.2 * Math.sqrt(Math.abs(x));  
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;  
        ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;  
        ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;  
        return ret;  
    }
    
    public static double transformLon(double x, double y) {  
        double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1  
                * Math.sqrt(Math.abs(x));  
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;  
        ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;  
        ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0  
                * pi)) * 2.0 / 3.0;  
        return ret;  
    }
    
    private double getCourse(double lat_a, double lng_a, double lat_b, double lng_b) {
        double d = 0;
        lat_a=lat_a*Math.PI/180;
        lng_a=lng_a*Math.PI/180;
        lat_b=lat_b*Math.PI/180;
        lng_b=lng_b*Math.PI/180;
       
         d=Math.sin(lat_a)*Math.sin(lat_b)+Math.cos(lat_a)*Math.cos(lat_b)*Math.cos(lng_b-lng_a);
        d=Math.sqrt(1-d*d);
        d=Math.cos(lat_b)*Math.sin(lng_b-lng_a)/d;
        d=Math.asin(d)*180/Math.PI;
       
//      d = Math.round(d*10000);
        return d;
     }
}
